The nation's economy grew at a robust 3.1 percent annual rate during the July-September quarter, but many analysts believe a slowdown is in store as the Asian financial crisis curbs U.S. sales overseas.

The Commerce Department said Tuesday growth in the gross domestic product - the total output of goods and services in the United States - was little changed from the April-June 3.3 percent rate.But despite its continued strength, the economy so far has not heated price pressures. Although labor shortages are increasing, inflation is nearly nonexistent. In fact, a measure tied to the GDP rose just 1.4 percent at an annual rate, the smallest increase in five years.

Earlier in the year, many analysts had predicted economic growth would begin to slow appreciably during third quarter.

Instead, it continued at nearly the same rate of the April-June quarter, although that was down from an even stronger 4.9 percent in the January-March period, the department said in its final revision of third-quarter data.

Still, many expect the financial turmoil in Asia to curb economic growth during 1998 and keep the Federal Reserve from raising short-term interest rates to prevent renewed inflation. They are forecasting a growth rate of between 2 percent and 2.5 percent.